Bag valve



Oct. :30, 195] STRAUSS 2,573,230

BAG VALVE Filed Jun 11, 1948 INVENTOR. Afl CH/IEL JI STRAUSS ATTORNEYS Patented Oct. 30, 1951 UNITED STAT- ES PATENT UE-Fl CE 2,573,230 V IBA'G VALVE Michael J. Strauss, ClevelandrOhio Application June 11,1948, Serial No. 32,422

4 Claims; 1

This invention relates to avalvebag. It has for its object the provision of an improved valve which willremain tight whenthe filling nozzle is withdrawn after loading the bag.

My invention is an improvementon the bag shown in Patent No. 2,378,285, issued June 1-2, 1945, to St. Regis Paper Company, as assignee of Theron A. Contryman. That patent discloses a valve provided -by the bag itself and a supplemental sheet within the'bag which-is intended to effect a closure when the filling spout'is withdrawn. 1 have found, however, that notwithstanding this additional sheet, troublesome leakage isliable to result from the bag. 'My experiments indicate that'this iscaused by two portions of the supplemental sheet'eoa'cting to form a'bridgeacrossthe valve-opening or fouling each otheras a result of the internal pressure when the filling spout is withdrawn.

I have found I can effectively prevent this bridging or fouling by providingtwo' differently formed tongues-at the inner portions'of the supplemental sheet, one of which tongues reacts differently to the internal pressure and closes in advance of the other. I prefer to make this'difference in the tongues by-cutting off one of the inwardly extending portions of the supplemental sheet with the'result that the remainder of that portion bends in more readily than the other portion and hence always precedes it as the two portions come together. Thus oneof these portions or tongues effectively overlaps the other as the valve closes.

My invention including the supplemental sheet having the provision above noted is illustrated in the'drawing hereof andis hereinafter more fully described and its essential novel features are set out in the claims.

In the drawings, Fig. l is aview of the valve corner of a bag, with parts brdken away to show the construction of the valve andits position in an empty bag; Fig. 2 is a plan view of the supplemental sheet which I employ to form a valve extension; Fig. 3 is a view illustrating the manner in which the supplemental sheet is inserted in the bag; Fig. 4 is a diagrammatic illustration of the action of one portion of the supplemental sheet in the act of folding over the other as the filling spout is withdrawn.

In the embodiment of the invention disclosed in the drawing, there is shown a bag It! having a gusseted side II, with a valve l2 constituting a portion of the bag itself, and folded in at the corner of the bag and at the end of the gusset. The end of the bag shown is closed by a reinforced stf'ip l3 attached by a line of stitching I4. ln addition to 'the'walls of the bag, which are turned' in' to forma'valve, there is the supplemental sheet 20 of this invention which constitutes a valve extension. This supplemental sheet is provided with a slot 2| along its center region leading from the free'end of the sheet anddefining a center line of fold, as indicated'by' the brokenline 22 on Fig. 2. -'The-line of 'fold 22 leaves two panels 23'and 24 in the supplemental sheet. Each of these panels-is furtherpartially divided by aslot, as 25 and 26, leading inwardly ashort distance from the free end of the sheet. The center slot'2l and the 'two side slots 25' and .26 leave between them two projecting tongues, namely, the tongue 21 between the sl0t'2l and the slot 25 and the tongue 28 between the slot 21 and the slot 25. The tongue 21 is formed with a right angle corn'er, as shown in Fig. 2, while the tongue 28'is cut off at approximately 45 from a regionnear the end of the slot 26 to a region which may be about the middle of the slot 2|. This formation'leaves thetongue 28 more readily flexible than the tongue Z'land hence when the filling spout is withdrawn the tongue 28 is bent transversely ahead of the tongue 21.

This supplemental sheet may be attached to the folded-in corner of the bag in any suitable manner, but the preferred method is merely to slip it in between the plies of the inturned cornerwhile the end of the bag is spread apart and the corner-foldedover, in the usual manner employed asthe first step in bottominga paperb'ag, as 'shown'in Fig. 3. K

"-The' rear'edges of the supplemental sheetare cuteif diagonally, as shown at 29, in Fig. 2, so as to fit'ire'adily against the slanting folds i5 0f"-l7hebag' flap I5. When in place the supplemental sheet may be permanently retained by the stitching I 4 of the reinforce l 3-which passes through the folded supplemental sheet in lines indicated at Main Fig. 2.

It will be readily understood that, when the bag is to be filled, a filling spout is inserted through the valve opening and spreads apart the sides of the valve and supplemental sheet. After the filling tube is withdrawn, the material in the bag presses the valve flap towards the seam. It is preferable to construct the valve so that the sides will spread apart along fold lines substantially half way between the bottom of the valve and the seam. Thereupon the lower portion of the flap folds upward and lies flatly against the upper portion of the flapv .vious one.

It will be readily understood that the peculiar formation described at the inner edge of the complete valve is advantageous regardless of whether it is produced by a supplemental sheet as shown or by an integral extension on the bag wall. Also the supplemental sheets applied in other ways than that illustrated. Also it will be readily understood that a supplemental sheet with a projecting valve edge of different shape than that shown might be positioned within the valve corner in the manner described above, provided that the projecting free portions of the two supplemental sheets are of such difierent dimensions, shape or area that one will be folded inwardly in advance of the other by the internal pressure in the bag as the filling spout is withdrawn.

While my improved construction is illustrated in connection with a bag having a gusset fold, it will be readily understood that a similar arrangement could be employed with a bag which would not have this gusset fold, the change being an ob- Furthermore, while the particular shaping of the attached edge of the supplemental sheet is desirable in a bag closed by a sewn seam and where the valve is normally collapsed in the manner illustrated in Fig. 1, it will be readily understood that a supplemental valve sheet may be placed in position in a bag corner of different form and the edges held differently, as for instance when end portions of the bag are folded over each other and pasted together in the usual manner for forming a pasted-end bag.

I claim:

1. A bag having one corner turned in to form a valve opening and a supplemental sheet mount ed in the pocket provided by the inturned corner of the bag and projecting inwardly beyond the same, such supplemental sheet being partially divided along the line of fold of the bag into two free-valve closing panels, each panel being partially sub-divided by a slot leading from the inner end of the panel to provide a pair of in tegral tongues in said panels respectively adapted to overlap each other consequent upon valveclosing motion of said panels, the distance along the line of fold on one tongue being greater than the distance along the line of fold on the other tongue, whereby the latter tongue is more readily bendable than the other to insure priority over said other tongue in valve-closing motion.

2. A bag having valve means in one corner comprising a sheet extending inwardly and having its free end portion divided by a central slot into two free valve-closing panels and each panel lap each other consequent upon the valve-closing motion of said panels, the comer of one of said tongues being cut awa along the line intersecting the central slot at a point intermediate the ends of the slot so as to provide a flaring slot, whereby one of said tongues continues at its inner edge for the full length of the slot and the other tongue has its inner edge substantially parallel with the first mentioned tongue for a distance and then flares away from such other tongue to insure priority of valve-closing action over said continuous tongue.

3. A bag having one corner turned in to form a valve opening and a supplementary sheet extending inward from said inturned corner, said sheet being normally folded along one line when the bag is empty and being folded along difierent lines to close the valve opening after the bag is filled, the edge of the sheet being provided with a partial slot along each of said lines and being unslit between said lines to form two tongues, one of said tongues continuing at its inner edge along the slit dividing the normal fold in a straight line to the end of the tongue and the other tongue having its inner edge diverted from said slot to widen the entrance to the slit, said tongues adapted to overlap in successive valve closing relation whereby said tongue having the diverted inner edge always precedes said other tongue in valve closing action, and the sheet being attached to the bag walls beyond the inturned corner and adjacent the slits along which the valve is folded after the bag is filled.

4. A bag having one corner turned in to form a valve opening, said inturned corner having a free end portion partially divided by a central slot into two free valve-closing panels and each panel further partially sub-divided by a slot parallel with the central slot to form a pair of integral tongues between the central slot and the sub-dividing slot respectively, said tongues adapted to overlap consequent upon valve-closing action of said panels, one of said tongues having the corner adjacent the central slot cut awa on a diagonal line extending from that slot to the end of the cut away panel to insure priority of valve-closing motion by said tongue.

MICHAEL J. STRAUSS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

